Touch panels and methods of manufacturing touch panels

ABSTRACT

A touch panel includes: a substrate having a first region and a second region. A plurality of sensing cells are disposed in the first region and a pad portion is disposed in the second region. An insulating interlayer is disposed on the plurality of sensing cells, a connection pattern is disposed on the insulating interlayer, with the connection pattern being electrically connected to adjacent sensing cells through contact holes. A transparent conductive pattern is disposed in the second region and on the insulating interlayer, with the transparent conductive pattern being electrically connected to the plurality of sensing cells and the pad portion.

CROSS REFERENCE TO RELATED APPLICATION

This application is a Divisional application of U.S. patent applicationSer. No. 14/502,512, filed on Sep. 30, 2014 and claims priority from andthe benefit of Korean Patent Application No. 10-2013-0122657 filed onOct. 15, 2013, which is hereby incorporated by reference for allpurposes as if fully set forth herein.

BACKGROUND Field

Exemplary embodiments of the present invention relate to touch panelsand methods of manufacturing touch panels. More particularly, exemplaryembodiments relate to touch panel having an improved reliability andmethods of manufacturing the same.

Discussion of the Background

A touch panel has been developed as an input device capable of inputtinginformation by converting a touch of an object into an electricalsignal. The touch panel may be classified into a resistive type touchpanel, a capacitive type touch panel, an electromagnetic type touchpanel, a surface acoustic wave (SAW) type touch panel, and an infraredtype touch panel. Currently, the capacitive type touch panel has beenprominently used in a wide range of fields due to a resolutiondifference, electrical characteristics, and durability.

The touch panel employed in a display device such as an organic lightemitting display (OLED) device or a liquid crystal display (LCD) devicemay generally recognize a contact position of the hand of a user or anobject though touch sensors thereof. As flexible display device has beenstudied, a touch panel having improved durability and reliability hasbeen researched, when touch panel is bent.

The above information disclosed in this Background section is only forenhancement of understanding of the background of the invention andtherefore it may contain information that does not form any part of theprior art nor what the prior art may suggest to a person of ordinaryskill in the art.

SUMMARY

Exemplary embodiments of the present invention provide a touch panelhaving an improved reliability.

Exemplary embodiments of the present invention also provide a method ofmanufacturing a touch panel having an improved reliability.

Additional features of the invention will be set forth in thedescription which follows, and in part will be apparent from thedescription, or may be learned by practice of the invention.

An exemplary embodiment of the present invention discloses a method ofmanufacturing a touch panel, the method including, forming a pluralityof sensing cells in a first region of a substrate, forming an insulatinginterlayer on the plurality of sensing cells, removing at least aportion of the insulating interlayer to form contact holes exposing theplurality of sensing cells, and forming a connection pattern and atransparent conductive pattern on the insulating interlayersimultaneously, wherein the connection pattern is electrically connectedto adjacent sensing cells, and the transparent conductive pattern isdisposed in a second region of the substrate outside of the firstregion.

An exemplary embodiment of the present invention also discloses a touchpanel including, a substrate including a first region and a secondregion, a plurality of sensing cells disposed in the first region, a padportion disposed in the second region, an insulating interlayer disposedon the plurality of sensing cells, a connection pattern disposed on theinsulating interlayer, the connection pattern being electricallyconnected to adjacent sensing cells through contact holes, and atransparent conductive pattern disposed in the second region and on theinsulating interlayer, the transparent conductive pattern beingelectrically connected to the plurality of sensing cells and the padportion.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory, andare intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention, andtogether with the description serve to explain the principles of theinvention.

FIG. 1 is a plan view illustrating a touch panel in accordance withexemplary embodiments.

FIG. 2 is the cross sectional view illustrating a touch panel of FIG. 1in accordance with exemplary embodiments.

FIG. 3 is a plan view illustrating a touch panel in accordance withexemplary embodiments.

FIG. 4 is the cross sectional view illustrating a touch panel of FIG. 3in accordance with exemplary embodiments.

FIG. 5 is a cross sectional view illustrating a touch panel inaccordance with exemplary embodiments.

FIGS. 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and 16 are plan views andcross sectional views illustrating a method of manufacturing a touchpanel in accordance with exemplary embodiments.

FIGS. 17, 18, 19, and 20 are plan views and cross sectional viewsillustrating a method of manufacturing a touch panel in accordance withexemplary embodiments.

FIGS. 21, 22, 23, 24, and 25 are plan views and cross sectional viewsillustrating a method of manufacturing a touch panel in accordance withexemplary embodiments.

FIGS. 26 and 27 are cross sectional views illustrating a method ofmanufacturing a touch panel in accordance with exemplary embodiments.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The exemplary embodiments are described more fully hereinafter withreference to the accompanying drawings. The invention may, however, beembodied in many different forms and should not be construed as limitedto the exemplary embodiments set forth herein. In the drawings, thesizes and relative sizes of layers and regions may be exaggerated forclarity.

It will be understood that when an element or layer is referred to asbeing “on,” “connected to” or “coupled to” another element or layer, itcan be directly on, connected or coupled to the other element or layeror intervening elements or layers may be present. In contrast, when anelement is referred to as being “directly on,” “directly connected to”or “directly coupled to” another element or layer, there are nointervening elements or layers present. Like or similar referencenumerals refer to like or similar elements throughout. As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items. It will be understood that for the purposesof this disclosure, “at least one of X, Y, and Z” can be construed as Xonly, Y only, Z only, or any combination of two or more items X, Y, andZ (e.g., XYZ, XYY, YZ, ZZ).

It will be understood that, although the terms first, second, third etc.may be used herein to describe various elements, components, regions,layers, patterns and/or sections, these elements, components, regions,layers, patterns and/or sections should not be limited by these terms.These terms are only used to distinguish one element, component, region,layer pattern or section from another region, layer, pattern or section.Thus, a first element, component, region, layer or section discussedbelow could be termed a second element, component, region, layer orsection without departing from the teachings of exemplary embodiments.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper,” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(rotated 90 degrees or at other orientations) and the spatially relativedescriptors used herein interpreted accordingly.

The terminology used herein is for the purpose of describing particularexemplary embodiments only and is not intended to be limiting of theinvention. As used herein, the singular forms “a,” “an,” and “the” areintended to include the plural forms as well, unless the context clearlyindicates otherwise. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

Exemplary embodiments are described herein with reference to crosssectional illustrations that are schematic illustrations ofillustratively idealized exemplary embodiments (and intermediatestructures) of the invention. As such, variations from the shapes of theillustrations as a result, for example, of manufacturing techniquesand/or tolerances, are to be expected. Thus, exemplary embodimentsshould not be construed as limited to the particular shapes of regionsillustrated herein but are to include deviations in shapes that result,for example, from manufacturing. The regions illustrated in the figuresare schematic in nature and their shapes are not intended to illustratethe actual shape of a region of a device and are not intended to limitthe scope of the invention.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this invention belongs. It will befurther understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art andwill not be interpreted in an idealized or overly formal sense unlessexpressly so defined herein.

FIG. 1 is a plan view illustrating a touch panel in accordance withexemplary embodiments, and FIG. 2 is a cross sectional view illustratingthe touch panel of FIG. 1 in accordance with exemplary embodiments. FIG.2 includes cross sectional views cut along line and line IV-IV′ in FIG.1.

Referring to FIGS. 1 and 2, the touch panel in accordance with exemplaryembodiments may include a substrate 100, a first sensing electrode 118,a second sensing electrode 119, a first wiring 174, a second wiring 176,and a pad portion 107.

The substrate 100 may include a transparent insulation substrate. Forexample, the substrate 100 may include a glass substrate, a quartzsubstrate, a transparent resin substrate, etc. The substrate 100 may bedivided into a first region I and a second region II. In exemplaryembodiments, the first region I may be a sensing region in which thesensing electrodes 118 and 119 may be located, and the second region IImay be a peripheral region in which the wirings 174 and 176, and the padportion 107 may be located. For example, the second region II maysurround at least one side of the first region I.

A buffer layer 105 may be disposed on the substrate 100. For example,the buffer layer 105 may include a transparent resin such aspolycarbonate-based resin. Alternatively, when the substrate 100includes the transparent resin substrate, the buffer layer 105 may beomitted.

A plurality of first sensing electrodes 118 and a plurality of secondsensing electrodes 119 may be disposed in the first region I on thesubstrate 100. In exemplary embodiments, the plurality of first sensingelectrodes 118 may be arranged in a first direction, and each of thefirst sensing electrodes 118 may extend in a second directionsubstantially perpendicular to the first direction. In this exemplaryembodiment, the plurality of second sensing electrodes 119 may bearranged in the second direction, and each of the second sensingelectrodes 119 may extend in the first direction.

Each of the first sensing electrodes 118 may include a plurality offirst sensing cells 112 and a plurality of first connection patterns152. In exemplary embodiments, each of the first connection patterns 152may connect the first sensing cells 112 in the second direction.

Each of the second sensing electrodes 119 may include a plurality ofsecond sensing cells 114 and a plurality of second connection patterns116. In exemplary embodiments, each of the second connection patterns116 may connect the second sensing cells 114 in the first direction.

A first wiring connection pattern 122 and a second wiring connectionpattern 124 may be disposed in the second region II on the buffer layer105. In exemplary embodiments, the first wiring connection pattern 122may be electrically connected to the first sensing electrode 118, andthe second wiring connection pattern 124 may be electrically connectedto the second sensing electrode 119.

In this exemplary embodiment, the first sensing cells 112, the secondsensing cells 114, the second connection pattern 116, the first wiringconnection pattern 122, and the second wiring connection pattern 124 maybe disposed on the buffer layer 105. Particularly, the second sensingcells 114, the second connection pattern 116, and the second wiringconnection pattern 124 may be integrally formed as illustrated inFIG. 1. In exemplary embodiments, the first sensing cells 112, thesecond sensing cells 114, the second connection pattern 116, the firstwiring connection pattern 122, and the second wiring connection pattern124 may include a plurality of metal nanowires. The plurality of metalnanowires may be arranged in a predetermined direction or may bearranged to form an irregular network.

In exemplary embodiments, the metal nanowires may have a width of about10 nm to about 50 nm, and may have a length of about 1 μm to about 10μm. For example, the metal nanowires may include Ag nanowires. The metalnanowires may have a relatively large length, and may be arranged toform the network, so that the first sensing cells 112, the secondsensing cells 114, the second connection pattern 116, the first wiringconnection pattern 122, and the second wiring connection pattern 124 mayhave a relatively small electrical resistance and a relatively highlight transmittance. Further, the metal nanowires may have a relativelylarge ductility, so that even when the touch panel is bent, the secondsensing cells 114, the second connection pattern 116, the first wiringconnection pattern 122, and the second wiring connection pattern 124 maynot be broken.

The first insulating interlayer 130 may be disposed on the first sensingcells 112, the second sensing cells 114, the second connection pattern116, the first wiring connection pattern 122, and the second wiringconnection pattern 124. For example, the first insulating interlayer 130may include a transparent resin such as acryl-based resin. Thetransparent resin may be disposed not only on top surfaces of the firstsensing cells 112, the second sensing cells 114, the second connectionpattern 116, the first wiring connection pattern 122, and the secondwiring connection pattern 124, but also at an empty space between themetal nanowires. Therefore, the first insulating interlayer 130 mayprotect and hold the metal nanowires.

The second insulating interlayer 140 may be disposed to cover the firstinsulating interlayer 130. The second insulating interlayer 140 mayinclude a transparent resin such as acryl-based resin. The secondinsulating interlayer 140 may protect the first sensing cell 112, etc.from an etching solution during an etching process for forming a contactholes which will be described as follow.

Referring now to FIG. 2, the first connection pattern 152 may beelectrically connected to the adjacent first sensing cells 112 throughthe contact holes. The first connection pattern 152 may overlap thesecond connection pattern 116, when viewed in a direction perpendicularto a top surface of the substrate 100. However, the first connectionpattern 152 and the second connection pattern 116 may be electricallyisolated from each other by the second insulating interlayer 140.

The first connection pattern 152 may include a transparent conductivematerial such as indium zinc oxide (IZO) or indium tin oxide (ITO).Therefore, the first connection pattern 152 may have a relatively smallelectrical resistance and a relatively high light transmittance.

Further, the first wiring 174 and the second wiring 176 may be disposedon the second insulating interlayer 140. The first wiring 174 and thesecond wiring 176 may be electrically connected to the first wiringconnection pattern 122 and the second wiring connection pattern 124,respectively, by the contact holes penetrating the second insulatinginterlayer 140 and the first insulating interlayer 130. That is, thefirst wiring 174 may electrically connect the first sensing electrodes118 with the pad portion 107, and the second wiring 176 may electricallyconnect the second sensing electrodes 119 with the pad portion 107. Thefirst wiring 174 and the second wiring 176 may be disposed on the secondinsulating interlayer 140 including the transparent resin, so that thefirst wiring 174 and the second wiring 176 may have an improveddurability compared to the case in which wirings are disposed directlyon the substrate 100. According to the present exemplary embodiment,when the touch panel is bent, the first insulating interlayer 130 andthe second insulating interlayer 140 including the transparent resin mayalleviate or relieve an external impact or a stress.

In exemplary embodiments, the first wiring 174 may include a firsttransparent conductive pattern 154 and a metal pattern 164 which may bestacked sequentially. For example, the first transparent conductivepattern 154 may include a material substantially same as to that of thefirst connection pattern 152, and the metal pattern 164 may include ametal such as copper or aluminum.

A transparent insulation layer or an encapsulation substrate (notillustrated) may be further disposed on the second insulating interlayer140, the first connection pattern 152, and the metal pattern 164.

According to exemplary embodiments, the touch panel may include theplurality of first sensing electrodes 118, and each of the first sensingelectrodes 118 may include the plurality of first sensing cells 112 andthe plurality of first connection pattern 152. The first connectionpattern 152 may be electrically connected to the adjacent first sensingcells 112 through the contact holes penetrating the second insulatinginterlayer 140 and the first insulating interlayer 130. That is, thefirst sensing cells 112 may be protected by the second insulatinginterlayer 140 during an etching process for forming the firstconnection pattern 152. Further, the second wiring 176 may be disposedon the second insulating interlayer 140, so that the second insulatinginterlayer 140 including the transparent resin may alleviate or relievean external impact or a stress.

FIG. 3 is a plan view illustrating a touch panel in accordance withexemplary embodiments, and FIG. 4 is a cross sectional view illustratingthe touch panel of FIG. 3 in accordance with exemplary embodiments. FIG.4 includes cross sectional views cut along line and line IV-IV′ in FIG.3.

Referring to FIGS. 3 and 4, the touch panel may include a substrate 100,a first sensing electrode 118, a second sensing electrode 119, a firstwiring 175, a second wiring 176, and a pad portion 107. The touch panelin FIGS. 3 and 4 may be substantially same as or similar to the touchpanel in FIGS. 1 and 2 except for the first wiring 175.

The substrate 100 may include a transparent insulation substrate. Forexample, the substrate 100 may include a glass substrate, a quartzsubstrate, a transparent resin substrate, etc. The substrate 100 may bedivided into a first region I in which the sensing electrodes 118 and119 may be disposed and a second region II in which the wirings 175 and176 may be disposed.

In exemplary embodiments, a plurality of first sensing electrodes 118and a plurality of second sensing electrodes 119 may be disposed in thefirst region I of the substrate 100. Each of the first sensingelectrodes 118 may include a plurality of first sensing cells 112 and aplurality of first connection pattern 152, and each of the secondsensing electrodes 119 may include a plurality of second sensing cells114 and a plurality of second connection patterns 116.

The first insulating interlayer 130 and the second insulating interlayer140 may hold and protect the first sensing cells 112, the second sensingcells 114, and the second connection patterns 116.

The first wiring 175 and the second wiring 176 may be disposed on thebuffer layer 105. For example, the first wiring 175 may include a firstwiring pattern 123, a first transparent conductive pattern 158, and asecond metal pattern 164, and the second wiring 176 may also includeelements which may correspond to those of the first wiring 175. Thefirst wiring pattern 123 may be directly connected to first sensingcells 112 and the pad portion 107. Therefore, the first wiring 175 andthe second wiring 176 may have a multi layered structure, and may havean improved electrical conductivity.

FIG. 5 is a cross sectional view illustrating a touch panel inaccordance with exemplary embodiments. The touch panel in FIG. 5 may besubstantially same as or similar to the touch panel in FIGS. 3 and 4except for the first wiring 177.

In exemplary embodiments, the first wiring 177 may include a firstwiring pattern 123 and a first transparent conductive pattern 158. Thefirst wiring pattern 123 may be directly connected to the first sensingcells 112 and a pad portion. Therefore, the first wiring 177 may have adouble layered structure, and may have an improved electricalconductivity. The first wiring pattern 123 may be formed simultaneouslyduring the process for forming the first sensing cells 112, and thefirst transparent conductive pattern 158 may be formed simultaneouslyduring the process for forming the first connection pattern 152.Therefore, the process for forming the first wiring 177 may besimplified.

FIGS. 6 to 16 are plan views and cross sectional views illustrating amethod of manufacturing a touch panel in accordance with exemplaryembodiments. FIGS. 6, 8, 10, 11, 12, 14, 15, and 16 illustrate crosssectional views cut along line and line IV-IV′ in the plan views.

Referring to FIG. 6, a buffer layer 105, a metal nanowire layer 110, andinsulation interlayer 130 may be formed on a substrate 100.

The substrate 100 may include a transparent insulation substrate. Forexample, the substrate 100 may include a glass substrate, a quartzsubstrate, a transparent resin substrate, etc. The substrate 100 may bedivided into a first region I and a second region II. In exemplaryembodiments, the first region I may be a sensing region in which sensingelectrodes 118 and 119 (See FIG. 7) may be located, and the secondregion II may be a peripheral region in which wirings 174 and 176 (SeeFIG. 13), and a pad portion 107 may be located.

The buffer layer 105 may be formed on the substrate 100. For example,the buffer layer 105 may include a transparent resin such aspolycarbonate-based resin. Alternatively, when the substrate 100includes the transparent resin substrate, the process for forming thebuffer layer 105 may be omitted.

The metal nanowire layer 110 may be formed on the buffer layer 105. Themetal nanowire layer 110 may be formed by; dispersing a plurality ofmetal nanowires in a solution, coating the solution on the buffer layer105, and dehydrating the solution. Therefore, the plurality of metalnanowires may be arranged to form an irregular network.

In exemplary embodiments, the solution may include at least one ofwater, alcohols, ketones, and ethers that may effectively disperse theplurality of metal nanowires, and may not corrode or oxidize theplurality of metal nanowires. The solution (that is, solvent) may have arelatively high volatility at a temperature above about 100° C.

In exemplary embodiments, the metal nanowires may have a width of about10 nm to about 50 nm, and may have a length of about 1 μm to about 10μm. Further, the metal nanowires may include, for example, Ag nanowires.The metal nanowires may have a relatively large length, and may bearranged to form the network, so that the metal nanowire layer 110 mayhave a relatively small electrical resistance and a relatively highlight transmittance. Further, the metal nanowires may have a relativelylarge ductility, So that even when the touch panel is bent, the metalnanowire layer 110 may not be broken.

Then, a first insulating interlayer 130 may be formed to cover the metalnanowire layer 110. In exemplary embodiments, the first insulatinginterlayer 130 may be formed using a transparent resin such asacryl-based resin. The transparent resin may be disposed not only on atop surface of metal nanowire layer 110, but also at an empty spacebetween the metal nanowires. For example, the first insulatinginterlayer 130 may have a thickness of about 80 nm to about 120 nm.

Referring to FIGS. 7 and 8, a first photoresist pattern 135 may beformed on the first insulating interlayer 130, and the metal nanowirelayer 110 and the first insulating interlayer 130 may be partiallyremoved.

The metal nanowire layer 110 may be patterned to form a plurality offirst sensing cells 112, a plurality of second sensing cells 114, and aplurality of second connection patterns 116 in the first region I, andto form a first wiring connection pattern 122 and a second wiringconnection pattern 124 in the second region II.

In this exemplary embodiment, the plurality of first sensing cells 112may be arranged in the first direction and a second directionsubstantially perpendicular to the first direction.

Further, the plurality of second sensing cells 114 may be arranged inthe first direction and the second direction. Each of the secondconnection patterns 116 may connect the adjacent second sensing cells114 in the first direction. Therefore, the plurality of second sensingcells 114 and the plurality of second connection patterns 116 mayconstitute a second sensing electrode 119. In exemplary embodiments, aplurality of second sensing electrodes 119 may be arranged in the seconddirection, and each of the second sensing electrodes 119 may extend inthe first direction.

In exemplary embodiments, one of the first sensing cells 112 disposed ata side end portion of the first region I may be electrically connectedto the first wiring connection pattern 122 disposed in the second regionII, one of the second sensing cells 114 disposed at a bottom end portionof the first region I may be electrically connected to the second wiringconnection pattern 124. However, the first wiring connection pattern 122and the second wiring connection pattern 124 may not directly contactthe pad portion 107.

In exemplary embodiments, the pad portion 107 may be formedsimultaneously during the process for forming the first and secondsensing cells 112 and 114. Alternatively, the pad portion 107 may beformed before or after forming the first and second sensing cells 112and 114.

The first photoresist pattern 135 may be removed through an ashingprocess or a strip process.

Referring to FIGS. 9 and 10, a second insulating interlayer 140 may beformed on the first insulating interlayer 130, and the second insulatinginterlayer 140 may be partially removed to form contact holes 142, 144,and 146.

The second insulating interlayer 140 may be formed using a transparentresin such as acryl-based resin. In exemplary embodiments, the secondinsulating interlayer 140 may be formed to cover the first insulatinginterlayer 130 in the first region I and the second region II. Inexemplary embodiments, the second insulating interlayer 140 may have athickness of about 1 μm to about 1.5 μm.

Then, the second insulating interlayer 140 may be partially etched toform the contact holes 142, 144, and 146 and expose some portions of thefirst insulating interlayer 130 overlapping the first sensing cells 112,the first wiring connection pattern 122, and the second wiringconnection pattern 124. Specifically, the first contact holes 142 mayexpose portions of the first insulating interlayer 130 which may overlapthe first sensing cells 112; the second contact holes 144 may exposeportions of the first insulating interlayer 130 which may overlap thefirst wiring connection pattern 122; and the third contact holes 146 mayexpose portions of the first insulating interlayer 130 which may overlapthe second wiring connection pattern 124. In other exemplaryembodiments, the contact holes 142, 144, and 146 may partially exposethe first sensing cells 112, the first wiring connection pattern 122,and the second wiring connection pattern 124.

Referring to FIG. 11, a plasma treatment process may be performed toremove exposed portions of the first insulating interlayer 130, andincrease a roughness of a surface of the second insulating interlayer140.

The plasma treatment process may be performed in an atmosphere includingan inert gas. For example, the plasma treatment process may be performedusing argon gas.

The plasma treatment process may partially remove the first insulatinginterlayer 130 exposed by the contact holes 142, 144, and 146, and thesecond insulating interlayer 140. Therefore, the contact holes 142, 144,and 146 may directly expose the first sensing cells 112, the firstwiring connection pattern 122, and the second wiring connection pattern124. Also the roughness of the surface of second insulating interlayer140 may be increased to improve the bonding strength with a transparentconductive layer. (See FIG. 12).

Referring to FIG. 12, a transparent conductive layer 150 and a metallayer 160 may be formed on a top surface of the second insulatinginterlayer 140 and inner walls of the contact holes 142, 144, and 146.

The transparent conductive layer 150 may be formed by an evaporationprocess or a sputtering process using a transparent conductive materialsuch as indium zinc oxide (IZO) or indium tin oxide (ITO). Therefore,the transparent conductive layer 150 may be electrically connected tothe first sensing cells 112, the first wiring connection pattern 122,and the second wiring connection pattern 124. Further, the secondinsulating interlayer 140 may have a rough surface, so that a bondingstrength between the second insulating interlayer 140 and thetransparent conductive layer 150 may be improved. That is, when thetouch panel is bent, the transparent conductive layer 150 may not belifted off. In exemplary embodiments, the transparent conductive layer150 may have a thickness of about 500 Å to about 1000 Å.

Therefore, the transparent conductive layer 150 may have a relativelysmall electrical resistance and a relatively high light transmittance.

The metal layer 160 may be formed by an evaporation process or asputtering process using a metal such as copper or aluminum. Inexemplary embodiments, the metal layer 160 may have a thickness about2000 Å to about 4000 Å. Therefore, the metal layer 160 may have arelatively small electrical resistance.

Referring to FIGS. 13 and 14, a second photoresist pattern 165 may beformed on the metal layer 160, and then the metal layer 160 and thetransparent conductive layer 150 may be partially removed.

The metal layer 160 and the transparent conductive layer 150 may bepartially etched using the second photoresist pattern 165 as an etchingmask. In exemplary embodiments, the metal layer 160 may be etched usinga first etching solution having a relative high etch rate about themetal layer 160, and then the transparent conductive layer 150 may beetched using a second etching solution having a relatively high etchrate about the transparent conductive layer 150. In other words, theetching process for the metal layer 160 and the etching process for thetransparent conductive layer 150 may be performed separately.

The transparent conductive layer 150 may be patterned to form a firstconnection pattern 152, a first transparent conductive pattern 154 and asecond transparent conductive pattern 156, simultaneously.

The first connection pattern 152 may be disposed in the first region I.The first connection pattern 152 may electrically connect the adjacentfirst sensing cells 112 through the first contact holes 142. Therefore,the first connection pattern 152 may serve as a bridge which mayelectrically connect the adjacent first sensing cells 112 in the seconddirection.

Accordingly, the plurality of first connection patterns 152 and theplurality of first sensing cells 112 may constitute a first sensingelectrode 118.

The first transparent conductive pattern 154 and the second transparentconductive pattern 156 may be disposed in the second region II. Thefirst transparent conductive pattern 154 and the second transparentconductive pattern 156 may be electrically connected to the first wiringconnection pattern 122 and the second wiring connection pattern 124,respectively. Therefore, the first transparent conductive pattern 154and the second transparent conductive pattern 156 may electricallyconnect the first sensing electrodes 118 and the second sensingelectrodes 119 with the pad portion 107, respectively.

The first connection pattern 152, the first transparent conductivepattern 154, and the second transparent conductive pattern 156 may bedisposed at the inner walls of the first contact holes 142, the secondcontact holes 144, and the third contact holes 146. Therefore, the firstsensing cells 112 may be protected by the first insulating interlayer130 and the second insulating interlayer 140 during the etching processfor forming the first connection pattern 152. In other words, the firstsensing cells 112 may not be exposed to an etching solution of theetching process, and the first sensing cells 112 may not be damaged bythe etching process, so that the touch panel may have an improvedreliability.

Further, the metal layer 160 may be patterned to form a first metalpattern 162 in the first region I and a second metal pattern 164 in thesecond region II. The first transparent conductive pattern 154 and thesecond transparent conductive pattern 156 and the second metal pattern164 in the second region II may constitute a wiring 174 having arelatively small electrical resistance.

Referring to FIG. 15, the second photoresist pattern 165 may be removed,and then a third photoresist pattern 166 may be form on the second metalpattern 164.

The second photoresist pattern 165 may be removed by an ashing processor a strip process. Then, the third photoresist pattern 166 may beformed to cover the second metal pattern 164 disposed in the secondregion II. That is, the third photoresist pattern 166 may expose thefirst metal pattern 162.

Referring to FIG. 16, the first metal pattern 162 is removed using thethird photoresist pattern 166 as an etching mask.

As the first metal pattern 162 may be removed, the metal patterns havinga relatively small light transmittance may be removed from the firstregion I. Therefore, the touch panel may have a relatively high lighttransmittance in the first region I.

According to exemplary embodiments, the first sensing cells 112, thesecond sensing cells 114, the second connection pattern 116, the firstwiring connection pattern 122, and the second wiring connection pattern124 may include the metal nanowires which may have a relatively largelength and may be arranged to form the network, so that the firstsensing cells 112, the second sensing cells 114, the second connectionpattern 116, the first wiring connection pattern 122, and the secondwiring connection pattern 124 may have a relatively small electricalresistance and a relatively high light transmittance. Further, the firstsensing cells 112 may be protected by the first insulating interlayer130 and the second insulating interlayer 140 during the etching processfor forming the first connection pattern 152. That is, the first sensingcells 112 may not be damaged during the etching process, so that aconnection between the first connection pattern 152 and the firstsensing cells 112 may have an improved reliability. The firsttransparent conductive pattern 154 and the second transparent conductivepattern 156 may be formed simultaneously during the process for formingthe first connection pattern 152. The first transparent conductivepattern 154 and the second metal pattern 164 in the second region II mayconstitute the first wiring having a relatively small electricalresistance.

FIGS. 17 to 20 are plan views and cross sectional views illustrating amethod of manufacturing a touch panel in accordance with exemplaryembodiments. The method of manufacturing the touch panel in FIGS. 17 to20 may be substantially same as or similar to the method described withreference to FIGS. 6 to 16.

The processes of present exemplary embodiment are substantially same asor similar to those of FIGS. 6 to 11. In other words, a metal nanowirelayer and a first insulating interlayer 130 may be formed on a substrate100 having a first region I and a second region II, and the metalnanowire layer and the first insulating interlayer 130 may be patternedto form first sensing cells 112, second sensing cells 114, secondconnection pattern 116, first wiring connection pattern 122, and secondwiring connection pattern 124. Then, a second insulating interlayer 140may be formed to cover the first insulating interlayer 130, and then thesecond insulating interlayer 140 may be partially removed to formcontact holes 142 and 144. A plasma treatment process may be performedto remove portions of the first insulating interlayer 130, and toincrease a roughness of the surface of the second insulating interlayer140.

Referring to FIG. 17, a transparent conductive layer 150 and a metallayer 160 may be formed on a top surface of the second insulatinginterlayer 140 and inner walls of the contact holes 142 and 144.Processes for forming the transparent conductive layer 150 and the metallayer 160 may be substantially the same as those of FIG. 12.

Referring to FIGS. 18 and 19, a second photoresist pattern 167 may beformed on the metal layer 160, and then the metal layer 160 and thetransparent conductive layer 150 may be partially removed.

In exemplary embodiments, a photoresist layer may be formed on the metallayer 160, and the photoresist layer may be selectively exposed anddeveloped using a halftone mask or a slit mask, thereby forming thesecond photoresist pattern 167. Therefore, the second photoresistpattern 167 may include at least two portions which may have differentthicknesses. For example, the second photoresist pattern 167 may includea first thickness portion 168 in the first region I and a secondthickness portion 169 in the second region II. In this exemplaryembodiment, the second thickness portion 169 may be thicker than thefirst thickness portion 168.

Then, the transparent conductive layer 150 may be partially removedusing the second photoresist pattern 167 as an etching mask, therebyforming a first connection pattern 152, a first transparent conductivepattern 154, and a second transparent conductive pattern 156,simultaneously. Further, the metal layer 160 may be partially removedusing the second photoresist pattern 167 as an etching mask, therebyforming a first metal pattern 162 and a second metal pattern 164.

Referring FIG. 20, the first thickness portion 168 of the secondphotoresist pattern 167 may be removed, and then the first metal pattern162 may be removed using the second thickness portion 169 of the secondphotoresist pattern 167.

The second photoresist pattern 167 may be partially removed. In thisexemplary embodiment, the first thickness portion 168 having arelatively small thickness may be sufficiently removed, while the secondthickness portion 169 may be partially removed. Therefore, the secondthickness portion 169 may cover the second metal pattern 164.

Then, the first metal pattern 162 is removed using the second thicknessportion 169 of the second photoresist pattern 167 as an etching mask. Inthis exemplary embodiment, the second metal pattern 164 may not beremoved.

Then, an ashing process or a strip process may be performed to removethe second thickness portion 169 of the second photoresist pattern 167.

According to exemplary embodiments, the second photoresist pattern 167may be formed using the halftone mask or the slit mask. Therefore, themetal layer 160 and the transparent conductive layer 150 may bepatterned to have different shapes using the second photoresist pattern167.

FIGS. 21 to 25 are plan views and cross sectional views illustrating amethod of manufacturing a touch panel in accordance with exemplaryembodiments. The method of manufacturing the touch panel in FIGS. 21 to25 may be substantially same as or similar to the method described withreference to FIGS. 6 to 16.

The processes of present exemplary embodiment are substantially same asor similar to those of FIG. 6. In other words, a buffer layer 105, ametal nanowire layer, and a first insulating interlayer 130 may beformed on a substrate 100 having a first region I and a second regionII.

Referring to FIGS. 21 and 22, a first photoresist pattern 135 is formedon the first insulating interlayer 130, and the metal nanowire layer andthe first insulating interlayer 130 may be partially removed using thefirst photoresist pattern 135.

In exemplary embodiments, the metal nanowire layer and the firstinsulating interlayer 130 may be patterned to form a plurality of firstsensing cells 112, a plurality of second sensing cells 114, and aplurality of second connection patterns 116 in the first region I, andto form a first wiring pattern 123 and a second wiring pattern 125 inthe second region II.

In exemplary embodiments, the first wiring pattern 123 may electricallyconnect the first sensing cell 112 disposed at a side end portion of thefirst region I with a pad portion 107 in the second region II. Further,the second wiring pattern 125 may electrically connect the secondsensing cell 114 disposed at a bottom end portion of the first region Iwith the pad portion 107 in the second region II.

On the other hand, the plurality of first sensing cells 112, theplurality of second sensing cells 114, and the plurality of secondconnection pattern 116 may be substantially same as or similar to thoseillustrate in FIGS. 7 and 8,

Referring to FIG. 23, a second insulating interlayer 140 may be formedon the first insulating interlayer 130, and the second insulatinginterlayer 140 may be partially removed to form contact holes 142 andopenings 145. Then, a plasma treatment process may be performed toremove an exposed portion of the first insulating interlayer 130, and toincrease a roughness of a surface of the second insulating interlayer140.

The second insulating interlayer 140 may be formed using a transparentresin such as acryl-based resin. In exemplary embodiments, the secondinsulating interlayer 140 may be formed to cover the first insulatinginterlayer 130 in the first region I and the second region II.

Further, the second insulating interlayer 140 may be partially etched toform the contact holes 142 exposing some portions of the firstinsulating interlayer 130 which may overlap the plurality of firstsensing cells 112, and to form the openings 145 exposing other portionsof the first insulating interlayer 130 which may overlap the firstwiring pattern 123 and the second wiring pattern 125.

Then, a plasma treatment process may be performed to remove the firstinsulating interlayer 130. Therefore, the contact holes 142 may exposethe plurality of first sensing cells 112, and the openings 145 mayexpose the first wiring pattern 123 and the second wiring pattern 125.

Referring to FIG. 24, a transparent conductive layer 150 and a metallayer 160 may be formed on a top surface of the second insulatinginterlayer 140 and inner walls of the contact holes 142 and the openings145, and a second photoresist pattern 165 may be formed on the metallayer 160. Then, the transparent conductive layer 150 and the metallayer 160 may be patterned using the second photoresist pattern 165 asan etching mask, thereby forming a first connection pattern 152, a firsttransparent conductive pattern 158, a first metal pattern 162, and asecond metal pattern 164.

In exemplary embodiments, the first wiring pattern 123, the firsttransparent conductive pattern 158 and the second metal pattern 164 maybe stacked sequentially. In other words, the first wiring pattern 123,the first transparent conductive pattern 158, and the second metalpattern 164 may have a multi layered structure. Therefore, the wiringmay have a relatively low electrical resistance and may have an improvedreliability.

Then, the second photoresist pattern 165 may be removed through anashing process or a strip process.

Referring to FIG. 25, a third photoresist pattern 166 may be formed onthe second metal pattern 164, and the first metal pattern 162 may beremoved using the third photoresist pattern 166. The process forremoving the first metal pattern 162 may be substantially same as orsimilar to those illustrated in FIGS. 15 and 16.

FIGS. 26 and 27 are cross sectional views illustrating a method ofmanufacturing a touch panel in accordance with exemplary embodiments.The method of manufacturing the touch panel in FIGS. 26 to 27 may besubstantially same as or similar to the method described with referenceto FIGS. 6 to 16.

The processes of present exemplary embodiments are substantially same asor similar to those of FIGS. 6 to 10. In other words, a buffer layer105, a metal nanowire layer, and a first insulating interlayer 130 maybe formed on a substrate 100 having a first region I and a second regionII, and the metal nanowire layer and the first insulating interlayer 130may be patterned to form first sensing cells 112, second connectionpattern 116, and first wiring connection pattern 122.

Referring to FIG. 26, a second insulating interlayer 140 may be formedto cover the first insulating interlayer 130, and then the secondinsulating interlayer 140 may be partially removed to form contact holes142 and openings 145. A plasma treatment process may be performed toremove portions of the first insulating interlayer 130, and to increasea roughness of a surface of the second insulating interlayer 140.

Referring to FIG. 27, a transparent conductive layer 150 may be formedon a top surface of the second insulating interlayer 140 and an innerwall of the contact holes 142 and the openings 145, and a secondphotoresist pattern 165 may be formed on the transparent conductivelayer 150. Then, the transparent conductive layer 150 may be patternedusing the second photoresist pattern 165 as an etching mask forming afirst connection pattern 152 and a first transparent conductive pattern158.

The first connection pattern 152 may be formed in the first region I,and the first transparent conductive pattern 158 may be formed in thesecond region II. The first transparent conductive pattern 158 and thefirst wiring pattern 123 may be stacked sequentially, and may constitutea wiring for connecting the first sensing cells 112 with the pad portion107. The wiring including the first transparent conductive pattern 158and the first wiring pattern 123 may have a double layered structure, sothat the wiring may have a relatively low electrical resistance and mayhave an improved reliability.

According to present exemplary embodiment, the first wiring pattern 123may be formed simultaneously during the process for forming the firstsensing cells 112, and the first transparent conductive pattern 158 maybe formed simultaneously during the process for forming the firstconnection pattern 152. Therefore, the process for forming the wiringmay be simplified.

The foregoing is illustrative of exemplary embodiments, and is not to beconstrued as limiting thereof. Although a few exemplary embodiments havebeen described, those skilled in the art will readily appreciate thatmany modifications are possible in the exemplary embodiments withoutmaterially departing from the novel teachings and advantages ofexemplary embodiments. Accordingly, all such modifications are intendedto be included within the scope of exemplary embodiments as defined inthe claims. In the claims, means-plus-function clauses are intended tocover the structures described herein as performing the recited functionand not only structural equivalents but also equivalent structures.Therefore, it is to be understood that the foregoing is illustrative ofexemplary embodiments and is not to be construed as limited to thespecific embodiments disclosed, and that modifications to the disclosedexemplary embodiments, as well as other exemplary embodiments, areintended to be included within the scope of the appended claims. Theinvention is defined by the following claims, with equivalents of theclaims to be included therein.

What is claimed is:
 1. A touch panel, comprising: a substrate comprisinga first region and a second region; a plurality of sensing cellsdisposed in the first region; a pad portion disposed in the secondregion; an insulating interlayer disposed on the plurality of sensingcells; a connection pattern disposed on the insulating interlayer, theconnection pattern being electrically connected to adjacent sensingcells through contact holes; and a transparent conductive patterndisposed in the second region and on the insulating interlayer, thetransparent conductive pattern being directly connected to the pluralityof sensing cells and the pad portion, wherein the contact holes areformed through the insulating interlayer in the first region to exposeat least a part of the plurality of sensing cells disposed between theinsulating interlayer and the substrate, wherein the first region is asensing region configured to recognize touch input, wherein theplurality of sensing cells include a wiring pattern extending into thesecond region, wherein the wiring pattern directly contacts the padportion, and wherein the wiring pattern is disposed between thesubstrate and the insulating interlayer, and the wiring patterncomprises a plurality of metal nanowires, wherein the plurality of metalnanowires forms an irregular network.
 2. The touch panel of claim 1,further comprising a metal pattern disposed on and directly connected tothe transparent conductive pattern.
 3. The touch panel of claim 1,wherein the connection pattern and the transparent conductive patterncomprise the same material and have the same thickness.
 4. The touchpanel of claim 1, wherein the plurality of sensing cells comprises aplurality of metal nanowires arranged to form an irregular network.